The invention relates to a gas bag for vehicles.
Gas bags are well-known for preventing or at least significantly reducing injury of a vehicle occupant in case of an accident. Gas bags typically are, in an inflated state, cushion-shaped and have an inflation opening through which pressurized gas can be introduced into the interior of the gas bag, in order to inflate the gas bag from a compact, folded condition into the inflated condition. FIG. 1 shows an example of such gas bag which here is a passenger gas bag. Reference numeral 10 designates the gas bag which is connected to an inflator 12 arranged in a dashboard 14 of the vehicle. Inflator 12 provides pressurized gas which builds up an internal pressure P in the gas bag, such that the gas bag can provide a restraining action for a vehicle occupant 16.
During the restraining action of the gas bag 10, a moment M is exerted on a neck of the vehicle occupant. This moment M results from an action of the tensioned wall of the gas bag. The interior pressure P present in the gas bag exerts a force F on the wall portion which is situated around the head 18 of the vehicle occupant, resulting in moment M. This is in particular a problem for a smaller vehicle occupant which contacts the gas bag in a lower portion, so that a large portion of the gas bag extends above the head of the vehicle occupant.
From EP 1 439 096 B1 a gas bag forming a single cushion is known which has elongated indentations and local projections in a plane surface facing towards the occupant. With these indentations and local projections a load imbalance between head load and chest load due to membrane forces in the airbag fabric shall be reduced.